For this team, autonomic control of circulation is the
key interest. Blood pressure control is profoundly affected by spaceflight.
Results from SLS-1
and SLS-2 show that
approximately 60% of crewmembers cannot stand quietly for 10 minutes shortly
after flight, often due to problems with low blood pressure. What has happened
to control of the circulation in space that has led to these changes?

The Autonomic Nervous System Team (composed of investigators
Drs. Friedhelm
Baisch, Gunnar Blomqvist, Dwain
Eckberg, and David
Robertson) has proposed a comprehensive set of autonomic tests to look
at every aspect of autonomic circulatory control. One of the procedures
planned for Neurolab, microneurography, has generated considerable interest.
With microneurography, a very fine tungsten needle is inserted into the
crewmember's peroneal nerve near the knee. When the nerve tip is in a motor
fascicle, sympathetic nerve traffic to blood vessels in muscle can be recorded.
The payload specialist candidates for Neurolab spent two months at Vanderbilt
University learning this procedure.